This Light Detection and Ranging (LiDAR) classified (ASPRS LAS classifications) dataset
is a topographic survey conducted for the Task Order 007 Aerial Survey 2010 project.
This data was produced for the US Army Corps of Engineers (USACE) Joint Airborne Lidar
Bathymetry Technical Center of Expertise (JALBTCX). The LiDAR point cloud was flown
at a density sufficient to support a maximum final post spacing of 1 point per meter.
3001 International Inc. acquired flightlines between April 9 - 26, 2010. The Task
Order 007 Aerial Survey 2010 was collected under the guidance of a Professional Mapper/Surveyor.
The area of coverage includes portions of the coastline of Louisiana in the counties
of Lafourche, Plaquemines, and Terrebonne, and along the south coast of Lake Pontchartrain
in Jefferson and St. Charles counties. The area of coverage for Mississippi includes
the barrier islands in Harrison and Jackson counties.

These data depict the elevations at the time of the survey and are only accurate for
that time. Users should be aware that temporal changes may have occurred
since this data set was collected and some parts of this data may no longer represent
actual surface conditions. Users should not use this data for critical
applications without a full awareness of its limitations. Any conclusions drawn
from analysis of this information are not the responsibility of NOAA or any of its
partners. These data are NOT to be used for navigational purposes.

The ABGPS, IMU, and raw scans are integrated using proprietary software developed
by Optech and delivered with the Optech ALTM Gemini System. The resultant file is
in a LAS binary file format. The LAS file version 1.1 format can be easily transferred
from one file format to another. It is a binary file format that maintains information
specific to the LiDAR data (return#, intensity value, xyz, etc.). The resultant points
are referenced to the Geographic NAD83 horizontal datum and NAVD88 vertical datum.

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2009-05-27T00:00:00

The data is subjected to rigorous QA/QC according to the 3001 Inc. Quality Control
Plan and procedures. Very briefly, a series of quantitative and visual procedures
are employed to validate the accuracy and consistency of the data. Ground control
is established by 3001, Inc. and GPS-derived ground control points (GCPs) points in
various areas of dominant and prescribed land cover. These points are coded according
to landcover, surface material, and ground control suitability. A suitable number
of points are selected for calculation of a statistically significant accuracy assessment
as per the requirements of the National Standard for Spatial Data Accuracy. A spatial
proximity analysis is used to select edited LiDAR data points within a specified distance
of the relevant GCPs. A search radius decision rule is applied with consideration
of terrain complexity, cumulative error, and adequate sample size. Accuracy validation
and evaluation is accomplished using proprietary software to apply relevant statistical
routines for calculation of Root Mean Square Error (RMSE) and the National Standard
for Spatial Data Accuracy (NSSDA) according to Federal Geographic Data Committee (FGDC)
specifications.

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2010-07-01T00:00:00

The Airborne Global Position System (ABGPS), inertial measurement unit (IMU), and
raw scans are collected during the LiDAR aerial survey. The ABGPS monitors the xyz
position of the sensor and the IMU monitors the orientation of the aircraft. During
the aerial survey laser pulses reflected from features on the surface and are detected
by the receiver optics and collected by the data logger. GPS locations are based on
data collected by receivers on the aircraft and base stations on the ground. The ground
base stations are placed no more than 20 km radius from the flight survey area.

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2011-09-01T00:00:00

The NOAA Coastal Services Center (CSC) received classified data (ASPRS LAS classifications)
in las format. The files contained LiDAR intensity and elevation measurements. CSC
performed the following processing for data storage and Digital Coast provisioning
purposes: 1. The data were converted from NAVD88 heights to ellipsoid heights using
Geoid03. 2. The LAS header fields were sorted by latitude and updated.

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2011-09-22T00:00:00

The NOAA National Geophysical Data Center (NGDC) received lidar data files via ftp
transfer from the NOAA Coastal Services Center. The data are
currently being served via NOAA CSC Digital Coast at http://www.csc.noaa.gov/digitalcoast/.
The data can be used to re-populate the system. The data are archived in LAS
or LAZ format. The LAS format is an industry standard for LiDAR data developed by
the American Society of Photogrammetry and Remote Sensing (ASPRS); LAZ is a loseless
compressed version of LAS developed by Martin Isenburg (http://www.laszip.org/). The
data are exclusively in geographic coordinates (either NAD83 or ITRF94). The data
are referenced vertically to the ellipsoid (either GRS80 or ITRF94), allowing for
the ability to apply the most up to date geoid model when transforming to orthometric
heights.